Magic Item Formula Discovery
A magic item recipe is called a formula.
A completed formula records the knowledge needed to craft a specific magic item: required tools, required skill, crafting time, resource burden, physical components, magical components, essence requirements, substitutions, workspace needs, and special restrictions.
Common and Uncommon formulas are usually available through ordinary magical practice, surviving craft traditions, apprenticeships, experimentation, or common institutional knowledge.
Rare, Very Rare, and Legendary formulas are different. In the ruined world of Andórë, characters usually cannot buy these recipes from a shop or copy them from a convenient guild manual. A powerful formula must normally be recovered, reconstructed, researched, reverse-engineered, or created through original invention.
ACS recipes describe what a completed formula looks like. Formula Development describes how characters learn, recover, or create one.
Formula Development¶
Formula Development has two main paths:
| Path | Meaning | Usual Source |
|---|---|---|
| Formula Discovery | Reconstructing a formula from evidence | Scraps, clues, examples, ruins, partial formulae, damaged items, inscriptions, teachers, or recovered notes |
| Original Formula Design | Creating a formula from scratch | Master craftsmanship, Arcana, theory, experimentation, and long-term invention |
Use Formula Discovery when the characters have evidence.
Use Original Formula Design when a master craftsperson is trying to invent the formula without enough evidence to reconstruct it.
When Formula Development Is Required¶
Formula Development is normally required when a character wants to craft:
- a Rare magic item;
- a Very Rare magic item;
- a Legendary magic item;
- an item using unusual substitutions;
- an item outside the crafter’s tradition;
- an item based on a lost, divine, planar, ancient, or unique magical principle;
- or any magic item the DM rules is not commonly understood.
The DM may waive Formula Development if the party already possesses a complete formula, learns it from a qualified teacher, recovers it from a reliable source, or has already crafted that exact item before.
Formula Development and Crafting Are Separate¶
Formula Development does not craft the item.
Formula Development answers the question:
“Do we know how to make this?”
Crafting answers the question:
“Do we have the materials, time, tools, skill, workspace, and components to actually make it?”
A character may discover or design a formula long before the party has the materials needed to use it.
Completed Formula¶
When Formula Development succeeds, the character produces a usable formula.
A completed formula records:
- required tools;
- required skill;
- crafting time;
- resource burden;
- physical components;
- magical components;
- essence requirements;
- valid specific component alternatives;
- known substitutions;
- required workspace conditions;
- and any special restrictions.
The character may now attempt to craft the item normally, provided the required materials, tools, workspace, time, and proficiencies are available.
Shared Formula Development Requirements¶
To attempt Formula Development, the lead researcher or craftsperson normally needs:
- proficiency in Arcana;
- proficiency with at least one tool relevant to the item;
- access to a suitable workspace;
- access to appropriate research materials, examples, clues, references, or experimental supplies;
- and time to work.
The relevant tool depends on the item.
Examples:
- Arcana + Smith’s Tools for a magic weapon or armor formula.
- Arcana + Jeweler’s Tools for rings, amulets, lenses, crowns, periapts, and gem-anchored items.
- Arcana + Alchemist’s Supplies for essence-heavy items, potions, oils, volatile reagents, and magical compounds.
- Arcana + Calligrapher’s Supplies for tattoos, spell diagrams, runic items, formula plates, scroll-adjacent items, and inscription-based formulae.
- Arcana + Herbalism Kit for plant-based potions, healing magic, restorative mixtures, and natural magical reagents.
- Arcana + Tinker’s Tools for small mechanisms, magical tools, clockwork, triggers, containers, and precision assemblies.
Formula Development Check¶
The Formula Development check is normally an Intelligence check using Arcana.
If the character is proficient with a relevant crafting tool, they may use that tool as part of the check. The DM may allow the tool proficiency to apply directly, or may allow the character to add the tool proficiency in addition to Arcana when the workspace and materials strongly support practical experimentation.
Progress Results¶
Both Formula Discovery and Original Formula Design use the same progress results.
| Check Result | Outcome |
|---|---|
| Success by 5 or more | Gain 2 formula progress. |
| Success | Gain 1 formula progress. |
| Failure | No progress. The time is spent, but no major materials are lost unless the DM says the experiment was risky. |
| Failure by 5 or more | No progress, and the work produces a complication. |
When the character reaches the required progress total, the formula is complete.
Formula Discovery¶
Formula Discovery is used when the characters are reconstructing a formula from evidence.
This evidence might include:
- a partial formula;
- a damaged magic item;
- an intact example of the item;
- inscriptions, diagrams, murals, spellbooks, or ritual records;
- surviving workshop notes;
- a related item from the same tradition;
- a teacher or specialist;
- a recovered relic;
- a known spell structure;
- a surviving temple, guildhall, academy, artificer lab, or ancient forge;
- or clues recovered through adventure.
Formula Discovery is research, reconstruction, reverse engineering, and controlled experimentation.
It is not invention from nothing.
Formula Discovery Requirements¶
To attempt Formula Discovery, the character needs:
- proficiency in Arcana;
- proficiency with at least one tool relevant to the item;
- access to a suitable workspace;
- access to research materials, examples, components, ruins, inscriptions, surviving records, or comparable clues;
- and time to experiment.
Discovery Tracks¶
Each work period, the character makes a Formula Discovery check. On a success, they gain progress. When they reach the required progress total, they create a usable formula.
| Item Rarity | Discovery Time per Check | Formula Progress Required | Discovery DC |
|---|---|---|---|
| Rare | 5 workdays | 3 progress | 18 |
| Very Rare | 10 workdays | 5 progress | 21 |
| Legendary | 25 workdays | 7 progress | 24 |
A workday is 8 hours of focused research, experimentation, drafting, testing, inscription, comparison, or controlled failure.
Research Advantages¶
The DM may grant advantage, reduce the DC by 2, or grant 1 automatic formula progress when the party has especially useful information.
Useful sources include:
- an intact example of the item;
- a damaged version of the item;
- a related item from the same tradition;
- a partial formula;
- a surviving workshop;
- a temple, guildhall, academy, artificer lab, or ancient forge;
- inscriptions, diagrams, murals, spellbooks, or ritual records;
- a teacher or specialist;
- a relevant spell known by the crafter;
- a rare material that clearly embodies the item’s function;
- or a successful adventure undertaken specifically to recover formula knowledge.
A complete and reliable formula removes the need for Formula Discovery.
Reverse Engineering¶
If the party possesses an existing magic item, they may attempt to reverse engineer its formula.
The item must be available throughout the discovery process. It does not need to be destroyed unless the character fails badly or chooses destructive examination.
Reverse engineering grants advantage on Formula Discovery checks if the item is intact and functional.
If the item is damaged, cursed, incomplete, counterfeit, corrupted, or from an alien tradition, the DM may instead reduce the DC by 2, grant only one automatic progress, or introduce complications.
Partial Formulas¶
A partial formula is useful but incomplete.
A partial formula may provide one of the following benefits:
- 1 automatic formula progress;
- advantage on one Formula Discovery check;
- the item’s required essence tag;
- the item’s required tool;
- one required physical component;
- one valid substitution;
- one known crafting hazard;
- or the correct crafting method.
Partial formulas are excellent treasure. They give players progress without handing them the entire answer.
Original Formula Design¶
Original Formula Design is used when a master craftsperson creates a magic item formula from scratch.
Formula Discovery starts with evidence.
Original Formula Design starts with mastery.
A master craftsperson may attempt to create a magic item formula using magical theory, practical experimentation, tool mastery, and long-term work.
This is not common research. It is invention.
Master Craftsperson Requirement¶
To design a formula from scratch, the lead craftsperson must have:
- proficiency in Arcana;
- proficiency with at least one required or highly relevant crafting tool;
- access to a suitable workshop;
- access to appropriate mundane and magical reference materials;
- and a Proficiency Bonus high enough for the item’s rarity.
| Formula Rarity | Minimum Proficiency Bonus | Typical Character Level |
|---|---|---|
| Rare | +4 | 9th level or higher |
| Very Rare | +5 | 13th level or higher |
| Legendary | +6 | 17th level or higher |
Common and Uncommon formulas are usually simple enough to derive through ordinary magical crafting practice, surviving craft traditions, or the normal recipe rules. Original Formula Design is mainly for Rare, Very Rare, and Legendary items.
Design Tracks¶
Original Formula Design is measured in months of focused work.
| Formula Rarity | Design Time per Check | Formula Progress Required | Design DC |
|---|---|---|---|
| Rare | 1 month | 3 progress | 18 |
| Very Rare | 1 month | 5 progress | 21 |
| Legendary | 1 month | 7 progress | 24 |
A month represents sustained work: theory, sketches, material tests, failed prototypes, small experiments, comparison to known formulae, tool trials, essence behavior studies, and controlled magical failures.
The month does not need to be spent in total isolation, but the craftsperson must have enough stability, workspace access, and uninterrupted time for meaningful progress.
Design Support¶
Original Formula Design can be improved by relevant support.
The DM may grant advantage, reduce the DC by 2, or grant 1 automatic formula progress if the craftsperson has one or more of the following:
- a related completed formula;
- an item with similar mechanics;
- a reliable theoretical text;
- access to an intact magical workshop;
- a surviving expert or institutional tradition;
- a rare material that strongly matches the item’s function;
- a relevant spell known by the craftsperson;
- a successful experiment using a lesser version of the effect;
- or a breakthrough gained through adventure.
This support does not remove the Proficiency Bonus requirement.
A lower-level craftsperson can help, gather clues, run tests, identify materials, or assist with Formula Discovery, but cannot lead the original design of a formula beyond their mastery.
Complications¶
When a Formula Development check fails by 5 or more, choose or roll a complication.
The same complication table can be used for either Formula Discovery or Original Formula Design. Interpret the result based on the path being used.
| d8 | Complication |
|---|---|
| 1 | A component, reagent, sample, note, test piece, or minor material is spoiled, consumed, cracked, burned, contaminated, or rendered useless. |
| 2 | The current theory is flawed. The next Formula Development check for this item is made with disadvantage unless the character spends an extra work period correcting it. |
| 3 | The experiment damages tools, workspace, containers, notes, or test materials, costing 1 Crafting Supply Unit to repair or replace. |
| 4 | The character identifies a missing requirement: a specific essence tag, material category, tool, spell, location, teacher, sample, or raw component is needed before progress can continue. |
| 5 | The magic behaves dangerously. The character must succeed on an appropriate saving throw or suffer a minor magical mishap. |
| 6 | The experiment attracts attention, leaves a magical trace, produces noise, smoke, light, dreams, omens, or another story consequence. |
| 7 | The current approach collapses. Lose 1 formula progress, minimum 0. |
| 8 | The character identifies a necessary adventure hook: a creature, place, relic, teacher, spell, planar condition, named material, or lost site is required before the formula can be completed. |
A complication should not usually end the project outright. Instead, it should reveal risk, cost, or the next thing the party needs to solve.
Delegated Formula Work¶
Characters may assign formula work to a qualified NPC, hireling, follower, institution, or crew specialist.
To make progress without direct player character involvement, the assigned researcher must have:
- proficiency in Arcana;
- proficiency with at least one relevant tool, or access to an effect that grants the needed tool proficiency;
- access to the research materials, partial formula, item sample, recovered clues, or theoretical resources;
- access to a suitable workspace;
- and enough uninterrupted time to work.
A magic item such as a Manifold Tool can satisfy the relevant Artisan’s Tool proficiency requirement while it is being used. It does not replace the Arcana proficiency requirement.
For Original Formula Design, a delegated researcher must also meet the Master Craftsperson Requirement for the formula’s rarity.
Delegated Discovery¶
Delegated Formula Discovery uses the normal Formula Discovery DC, time per check, progress requirements, and complication rules.
This is especially useful when the party is away from their ship, Bastion, stronghold, workshop, or settlement.
While the party adventures, the researcher may spend downtime making Formula Discovery checks. When the party returns, the DM reports the result:
- how much progress was made;
- whether any complications occurred;
- whether a missing component, essence, tool, spell, or location was identified;
- and what the researcher needs next.
This allows formula discovery to move forward without requiring the entire party to stay home and stare at notes.
Delegated Design¶
Delegated Original Formula Design is possible, but only if the assigned craftsperson is a true master.
The researcher must meet the Proficiency Bonus requirement for the formula’s rarity.
A shipboard arcanist, guild sage, artificer, temple smith, or hired specialist may be able to design Rare formulae. Very Rare and Legendary formulae require correspondingly greater mastery.
The DM decides whether an NPC is qualified.
Limits of Delegated Work¶
A delegated researcher cannot solve every problem from a desk.
The DM may rule that progress stalls until the party provides one or more of the following:
- a missing essence or raw component;
- a better sample of the item;
- a related magic item;
- a surviving inscription, diagram, or formula fragment;
- access to a specific site, forge, shrine, library, or ruin;
- a spell the item depends on;
- a named material;
- or information from a creature, spirit, institution, or expert.
When this happens, the researcher does not fail. They identify the next adventure hook.
Shipboard Example¶
Ethlohyn Ahmorath, the Dawn Seeker’s Ship’s Arcanist, is proficient in Arcana and has access to the ship’s alchemical stores. If she is also using a Manifold Tool, she can satisfy many Artisan’s Tool requirements while researching a formula aboard the ship.
While the party is adventuring, Ethlohyn can attempt Formula Discovery for an item, provided the party leaves her enough clues, samples, materials, and workspace to study.
If she succeeds, the party returns to useful progress or a completed formula.
If she fails badly, the party may return to spoiled reagents, damaged notes, a cracked sample, a smoking workbench, or the very ACS result of all time:
“I know what we need. Unfortunately, it is still inside something alive.”
Ethlohyn can only attempt Original Formula Design if the DM rules that she meets the Master Craftsperson Requirement for the item’s rarity.
Assistants¶
Assistants may contribute if they have Arcana proficiency, relevant tool proficiency, or a clearly useful specialty.
A qualified assistant may grant advantage on one Formula Development check per work period, provided the DM agrees their contribution is meaningful.
Assistants do not remove the need for a qualified lead researcher or craftsperson.
For Original Formula Design, assistants do not remove the Proficiency Bonus requirement.
DM Guidance¶
Formula Development should create adventures, not paperwork.
A Rare item formula might be solved through study, experimentation, and one useful clue.
A Very Rare item formula should probably require an expedition, special material, surviving teacher, ancient ruin, recovered example, or specialized workshop.
A Legendary item formula should be a campaign objective. It may require multiple sources of knowledge, named materials, planar relics, lost workshops, divine sites, ancient libraries, or the cooperation of powerful beings.
Original Formula Design should be possible, but not casual.
A 9th-level master can invent Rare item formulae.
A 13th-level master can invent Very Rare item formulae.
A 17th-level master can invent Legendary item formulae.
That does not mean they can invent anything from nothing in an empty room. The higher the rarity, the more likely the work should demand rare materials, dangerous tests, ancient theory, special locations, or adventure-driven breakthroughs.
A completed formula is a major reward. A Legendary formula may be as important as the item itself.
The goal is not to prevent crafting.
The goal is to make powerful crafting feel earned.